10 documents found, page 1 of 1
Drug discovery based on oxygen and nitrogen (non-)heterocyclic compounds develo...
Sousa, Joana L. C.; Albuquerque, Hélio M. T.; Silva, Artur M. S.Artur Silva's research group has a long history in the field of medicinal chemistry. The development of new synthetic methods for oxygen (mostly polyphenols, e.g., 2- and 3-styrylchromones, xanthones, flavones) and nitrogen (e.g., pyrazoles, triazoles, acridones, 4-quinolones) heterocyclic compounds in order to be assessed as antioxidant, anti-inflammatory, antidiabetic, and anticancer agents has been the main ...
2,2’-[(1E,1’E)-{[Hexa-2,4-diyne-1,6-diylbis(oxy)]bis(2,1-phenylene)}bis(ethene-...
Malafaia, Daniela; Sousa, Joana L. C.; Silva, Artur M. S.; Albuquerque, Hélio M. T.2-Styrylchromones (2-SCs) are interesting compounds for their biological properties as well as versatility as starting materials for further transformations. Herein, we disclose a new 2-SC derivative—2,2’-[(1E,1’E)-{[hexa-2,4-diyne-1,6-diylbis(oxy)]bis(2,1-phenylene)}bis(ethene-2,1- diyl)]bis(4H-chromen-4-one)—which is a dimeric compound formed by two units of 2-SC linked through a 1,3-diyne moiety. It was obta...
6-[(2S,3R)-3-(2,4-Difluorophenyl)-3-hydroxy-4-(1H-1,2,4-triazol-1-yl)butan-2-yl...
Sousa, Joana L. C.; Albuquerque, Hélio M. T.; Silva, Artur M. S.Voriconazole (VN) is an antifungal drug indicated for the treatment of several fungal infections. Due to its side effects, some works involving late-stage functionalization of VN have been reported in the literature. Here, we disclose a new VN derivative, the 6-[(2S,3R)-3-(2,4-difluorophenyl)- 3-hydroxy-4-(1H-1,2,4-triazol-1-yl)butan-2-yl]-5-fluoropyrimidine-4-carbaldehyde (VNCHO). This compound results from th...
Microwave-assisted synthesis of 4,6-disubstituted isoindoline-1,3-diones by Die...
Nouali, Fatiha; Sousa, Joana L. C.; Albuquerque, Hélio M. T.; Mendes, Ricardo F.; Almeida Paz, Filipe A.; Saher, Liza; Kibou, ZahiraThe synthesis of 4,6-disubstituted isoindoline-1,3-diones through microwave-assisted Diels-Alder (DA) reactions is reported. Chromones bearing an α,β-unsaturated carbonyl system at C-3 were used as dienes and a scope of maleimides as dienophiles was investigated. The proposed mechanism involves a DA reaction of 3-benzoylvinylchromones with different maleimides, followed by chromanone ring opening and in situ ox...
Mild synthesis of symmetric 3,5-disubstituted nitrobenzenes
Francisco, Telmo N.; Sousa, Joana L. C.; Guieu, Samuel; Silva, Artur M. S.; Albuquerque, Hélio M. T.A mild synthesis of 3,5-disubstituted nitrobenzenes from readily available 3-formylchromones is reported. The developed methodology follows a cascade process, promoted by 1,8-diazabicyclo[5.4.0]undec-7-ene. The proposed mechanism involves an initial Michael addition of nitromethane at C-2 of a 3-formylchromone. The resultant intermediate undergoes another Michael reaction with a second 3-formylchromone molecule...
Decoration of A-ring of a lupane-type triterpenoid with different oxygen and ni...
Sousa, Joana L. C.; Albuquerque, Hélio M. T.; Silvestre, Armando J. D.; Silva, Artur M. S.Betulinic acid (BA) was used as starting building block to create a library of novel BA-derived compounds containing O- and N-heterocycles. Firstly, BA was converted into methyl betulonate (BoOMe), which was used as intermediate in the developed methodologies. 1,2-Oxazine-fused BoOMe compounds were obtained in 12–25% global yields through a Michael addition of nitromethane to methyl (E)-2-benzylidenebetulonate ...
Catalytic one-pot diastereoselective Michael-initiated ring-closure of methyl k...
Sousa, Joana L. C.; Talhi, Oualid; Mendes, Ricardo F.; Almeida Paz, Filipe A.; Bachari, Khaldoun; Silva, Artur M. S.A one-pot diastereoselective base-catalyzed Michael-initiated ring-closure (MIRC) of activated methyl ketones with 3-bromochromones to give cyclopropa[b]chromanones is described. Three asymmetric centres are generated in the new cyclopropa[b]chromanone skeleton. Stereochemistry studies based on NMR spectroscopy and single-crystal X-ray diffraction analysis revealed the trans configuration of the cyclopropane ri...
Catalytic One-Pot Diastereoselective Michael-Initiated Ring-Closure of Methyl K...
Sousa, Joana L. C.; Talhi, Oualid; Mendes, Ricardo F.; Almeida Paz, Filipe A.; Bachari, Khaldoun; Silva, Artur M. S.A one-pot diastereoselective base-catalyzed Michael-initiated ring-closure (MIRC) of activated methyl ketones with 3-bromochromones to give cyclopropa[b]chromanones is described. Three asymmetric centres are generated in the new cyclopropa[b]chromanone skeleton. Stereochemistry studies based on NMR spectroscopy and single-crystal X-ray diffraction analysis revealed the trans configuration of the cyclopropane ri...
One-Pot Synthesis of Novel Highly Functionalized Furan-Based Polyphenolics
Sousa, Joana L. C.; Talhi, Oualid; Rocha, Djenisa H. A.; Pinto, Diana C. G. A.; Almeida Paz, Filipe A.; Bachari, Khaldoun; Kirsch, GilbertNovel, highly functionalized furan-based polyphenolics were prepared. The employed methodology involves a one-pot 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) catalyzed 1,4-conjugate addition of 1,3-dicarbonyl compounds on 3-bromochromones, furan heterocyclization, and chromanone ring opening.
A new supramolecular organic-inorganic adduct: {[Eu(CH(3)OH)(H(2)O)(8)](2) [Eu(...
Soares-Santos, Paula C. R.; Cunha-Silva, Luís; Sousa, Filipa L.; Sousa, Joana L. C.; Gates, Paul J.; Klinowski, Jacek; Trindade, Tito; Rocha, JoãoA new europium(III) supramolecular adduct constructed from alpha-Keggin-type [PW(12)O(40)](3-) anions, benzo-15-crown-5 and dibenzo-30-crown-10 molecules, {[Eu(CH(3)OH)(H(2)O)(8)](2)[Eu(H(2)O)(8)][PW(12)O(40)](3)}.8(C(14)H(20)O(5)). 2(C(28)H(40)O(10)).6(CH(3)OH).6(H(2)O), was prepared and its crystal structure determined by single-crystal X-ray diffraction. The compound was further characterized using FT-IR, FT...